Method of patching



Aug. 16, 1927. 1,639,082

J. C. DE P lNG METHOD OF P ING Filed July 19. 1926 2 Sheets-Sheet 1 INVENTOR. a 01111 C Penning ATTORNEY Aug. 16, 1927. 1,639,082

J. C. DE PENNING METHOD OF PATCHING Filed July 1926 2 Sheets-Sheet 2 H910 John 61%;?

Jim

Patented Aug. 16, 1927.

UNITED STATES:

1,639,082 PATENT OFFICE.

JOHN C. DE PENNING, OF PORTLAND, OREGON, ASSIGNOB TO CENTRAL DOOR AND LUMBER COMPANY, OF PORTLAND, OREGON, A CORPORATION.

METHOD 0] PATGHING.

Application fled July 18, 1926. Serial No. 123,572.

My invention relates to the art of woodworking, and has for its particular object the provision of a simple and efiicient method of patching boards having surface imperfections such as pitch pockets. My invention has particularly to do with the sash and door industry, because in the latter industry the finished product is sold according to grade and the grade is established by the number of surface imperfections present.

Much attention has been given to methods and devices for eliminating said imperfections and patching, but all patches as made at present, either increase the cost of the products produced to such a degree that any saving in grade is nullified by the increased cost of production, or else t e patching is done in such a manner that the patch is very apparent so that the product frequently has to retain the lower grade.

The most common method of atching is shown and described in the United States Patent, No. 1,005,546 granted to William C. Hobart. By this method the pitch pocket or other imperfection is cut away by an elongated incislon having relatively straight walls and square ends. The incision is formed by the kerf of a rotatable saw, and a one-piece plug corresponding in shape to the incision thus made is glued and driven into the latter.

This method is deficient in the following particulars 1. The square ended patches are very no ticeable, especially in vertical grain lumber, because it is impracticable to select a strip of patching material which corresponds so closely in grain spacing and in width that the grain of the wood can be matched exactly and thus the inserted patch is defined by the broken grain structure at each end.

2. It is necessary to give the plug inserted a slight amount of draft or taper so as to permit it to enter the vertical sided incision and thus the plug used does not correspond exactly in cross-section to the incision. The only portion of the side walls in contact with the plug is the surface edge with which the tapered plug engages and is secured thereto by glue.

It is customary to sandpaper or otherwise dress off the patched surface after the plug is secured in place and such surface ed e thus glued is frequently so shallow that t e method can be retained and the disadvantages heretofore noted eliminated by formin the incision substantiall wedge-shaped in cross-section and cigar-s aped in plan and forming the plug to be inserted therein, of a plurality of sections correspondin in cross section to said incision. That is, p ugs are used which are made u of a plurality of pieces also wedge-shape in section and said pieces are driven endwise and downwardly into theincision so that they are secured tightl in place along their entire widths and t us dressing the surface can not remove the securing means for the patch to permit the latter to drop out. Making the patch cigar-shaped in section, that is, having pointed ends, tends to eliminate any sharp break in grain structure for the reason that thebreak is distributed over a substantially larger area and the severing of the separate grains or annular rings is not in a transverse line.

I show in a co-pending application for patent entitled, Patching Saw, filed July 19th, 1926, Serial No. 123,571, a rotatable tool for forming said incision such saw being provided with teeth formed about its periphery such teeth forming a knife-edged cutting means in that the teeth diverge angularly at each side of the saw.

A further object of my invention is to provide a method of this character by which a minimum amount of material may be removed in forming an incision so that a smaller patch may be inserted.

Pitch pockets, especially, .are elongated and extend lengthwise of the grain and terminate in pointed ends and thus the saw thus described may form an incision exceeding the surface defect only slightly, and because of the angular divergence of the cut ting teeth of the patching saw the incision may be formed of a depth also exceeding that of the defect only slightly. By making the plug wedge-shaped in section and sectional I am able to use strips of patching material of uniform cross-section which will fill the incision exactly, independent of the depth of the latter, and the patch will vary only in the excess amount of material to be dressed off.

Further details of my improved patching method, are hereinafter set out with reference to the accompanying drawings, in which:

Fig. 1 is a side elevation of a board in which an incision is made, by my improved saw, to remove a surface defect;

Fig. 2 is a transverse sectional view thru such saw and board;

Fig. 3 is a pers ective view "of said board with the incision t us made and with a sectional patch super-imposed above the inci- Fig. 4c is a view similar to Fig. 1 with a three-piece sectional patch secured in place;

Fig. 5 is a fragmentary view of a board showing a pitch pocket.

Fig. 6 is a progressive perspective view of the above showing an lIlClSlOIl formed by my method to remove such pitch pocket;

Fig. 7 is a similar progressive fragmentary perspective view showing one-half of a sectional plug set loosely in place;

Fig. 8 is a similar progressive perspective view showing said sectional plug secured in place and with one-half thereof dressed off.

Fig. 9 is a similar progressive fragmentary perspective view showing the finished patch; and

a Fig. 10 is a sectional View taken on the line lO-lO in Fig. 7 transversely through the incision and thru the patch seated there- 1n.

In Fig. 5, ll show a pitch pocket a, which is the usual surface imperfection to be eliminated. The grain structure or annular rings I) tend to diverge about said pitch pocket to produce a wave or irregularity in the grain. That is, the pitch pocket a tends to space the grain structure or rings 6 wider than normal and thus even if a patch made from the same board is inserted, the grain structure will differ and the patch will be very noticeable. By my method a pitch pocket or other imperfection a is cut away by a cigar-shaped incision c or 0' which is only slightly greater than the defect so as to cut away a minimum amount of material. Such incision is wedge-shaped in cross-section, as shown in Figs. 2 and 10, and preferably is formed b a rotatable saw d having divergent teeth 2 formed about its periphery. Such teeth are beveled or diverge angularly along both sides of the saw blade as shown in Fig. 1, and thus cut away a wedge-shaped incision, and extend a substantial distance up both sides to permit an incision of considerable depth to be formed in the board.

As is evident, the further the saw is forced into the board the wider an incision will be formed, the walls of such incision, however,

diverging at a constant angle. To permit such saw to be movable to vary the depth of the cut, it is mounted upon a vertically adjustable shaft e and the board a to be acted upon is carried by a table f. Said table f may be moved and the saw fixed or be stationary and the saw movable longitudinally thereover, as well as vertically thereto.

In practice the teeth extend up the side of the saw about one inch and the saw is approximately five and one-half inches in diameter. Thus, pitch pockets up to about three inches in length can be cut away without moving the saw longitudinally relatively to the table but may be cutaway merely by moving the saw verticall thereto. short pitch pockets a two-p1ece plug. 9 can be used to fill the incision as is shown in Figs. 6 to 10, inclusive. To eliminate a pitch pocket of greaterlength, however, it is nec essary to move the saw relatively longitudinally of thetable' to produce an incision 0' and to fill such an incision with a three-piece plug 9'. That is, short pitch pockets can be eliminated merely by depressing the saw thus forming an incision 0 having a base port-ion which is angularly disposed towards the surface in two directions and making equally divergent angles to the surface in opposite directions. In the incision a, however, said an ular base portions 0 are connected by a base portion 0 which extends substantially parallel to the surface acted upon, and to patch an incision 0' it is necessary to use three pieces, one piece substantially the length of the base portion 0 and two other pieces substantially the length of each of the angular base portions 0, which extend towards the surface at each end of the incision.

With

ever, 1 preferably bevel the adjacent ends h as shown in Figs. 7 to 9 inclusive, so that there is no transverse break in the grain structure. A further purpose in beveling the adjacent ends of the sectional plug is that when said plug pieces are driven in place they are driven toward the base portion of the incision and also towards each other and su h beveled ends tend to form two engaging wedge-like faces which slide upon each oth r and lock the sectional plug lugis not easily detected, because conorms generally to the divergent CODdIUOIIS of'the grain structure at each side of the defect. ,i As has been brought out heretofore, m method permits patches to be used m whic the sides of the patch ma be made to coincide exactly-with the si e of the incision without requiring draft and yet the patches are made from continuous strips of glued pieces corresponding in grain structure and quality to the remainder of such surface, each of said pieces being correspondingly wedge-shaped in cross-section and of substantially greater width than the depth of such inclsion, one of said pieces being arran ed with one end seated further into the incision than the other so that its longitudinal centerline makes a substantial such angle with such surface and then forcing such latter piece endwise toward the other pieces and towards the base of such incision, whereby all of such pieces are see cured in said incision with their ends in abutment, dressing off the excess portion of such plug not fitted into the incision.

2. In the art of woodworking, the method of patching a board having a surface imperfection, consisting in cutting away such imperfection by forming an incision extending len vhwise of the grain of said board, and aving its oppositely disposed ends narrowing to points, and placing in the incision thus made a plug comprising a plurality of elongated glued pieces of uniform, wedge-shaped cross-section, and corresponding in grain structure and quality to the remainder of such surface and forcing such pieces endwise towards each other and towards the base of such incision, whereby such pieces are secured in said incision with their ends in abutment, dressing ofi the excess portion of lug not fitted into the incision.

121 the art of woodworking, the method of patching aboard having a surface imperfection, consisting in cutting away such imperfection by forming an incision extending lengthwise of the grain of said board, and having the ends of its base portion inclined towards the surface of away suc .c1s1on extending len hwise'of the grain of such board to make a substantially obtuse angle therewith, and placing in the incision thus made a plug comprising a plurality of elongated glued pieces corresponding in grain structure and quality to the remainder of such surface, and in length and in number to the angular portions of the base thus formed, one piece being arranged parallel to each' an ar base portion and then seating such pieces into such incision by forcing them endwise into the incision and relatively toward each other.

4. In .the art of woodworking, the

method of patching a board having a surface imperfection, consisting in: cutting imperfection byforming an in said board, and having the ends of its, base portion inclined towards the surface of such board to make a substantially obtuse angle therewith, the remainder of such base portion bein substantially parallel to such surface, an placin in the incision thus made a lu oomprismg a plurality of elongated g ue pieces corresponding in grain structure and quality -to the remainder of such surface and in length and in number to the angular portions of the base thus formed. each piece being arranged substantially parallel to its adjacent base portion, and then forcing the end pleces endwise towards each other and downwardly towards the remaining piece fitted into the parallel of such incision, where y such pieces are secured in said incision with their ends in abutment, dressin oil the excess portion of such plug not tted into t they are seated into the latte away such im erfections by forming an incision extending lengthwise .of the grain ortion of the base incision, as

5. In the art of woodworking, the method of patching a board having a surface imperfection, consisting in cutting y spectively, so that their beveled ends abut,

and forcing such pieces endwise towardseach other and towards the base of such incision, whereby such pieces are secured in said incision with their endsin abutment, dressing off the excess portion of such plug not fitted into the incision.

6. In the art of woodworking, the method of patching a board having asurface imper fection, consisting in cutting away such imperfection by forming an incision extending lengthwise of the grain of said board, we ge-shaped in cross section, and having its oppositely disposed ends narrowing to points, then placing in the incision thus made a lug comprising a plurality of elongated g ued pieces corresponding in grain structure and quality to the remainder of such surface, each of said pieces being corres ndingly wedge-shaped and of substantia 1y uniform cross-section and of substantially greater width than the depth of such' incision, and forcing such pieces endwise towards each other and towards the base of such incision, whereby such ieces are secured in said incision with their ends in abutment, dressing off the excess portion of such plug not fitted into the incision.

7. In the art of woodworking, the method of patching a board having a surface imperfection, consisting in cutting away such imperfection by forming an incision extending lengthwise of the grain of said board, wedge-shaped in cross-section, having its oppositely disposed ends narrowing to points and having the ends of its base portion inclined towards the surface of such board to .make a substantially obtuse angle therewith, the remainder of such base portion being substantially parallel to such surface, then placing in the incision thus made a plug comprising a plurality of elongated glued 1 pieces corresponding in grain structure and quality to the remainder of such surfaceand in length and in number to the angular portions of the base thus formed each piece being arranged substantially parallel to its adjacent base portion, and each of vsaid pieces being correspondingly wedge-shaped and of substantially uniform cross-section and of substantially greater width than the depth of such incision, then forcing such end' pieces towards each other and downwardly towards the remaining piece fitted into the parallel portion of the base of such incision, whereby such pieces are secured in said incision with their ends in abutment, dressing off the excess portion of such plug not fitted into the incision.

8. In the art of woodworking, the method of patching a board having a surface iniperfection, consisting in cutting away such imperfection by forming an inclsion extending lengthwise of the grain of said board, Wedge-shaped in cross-section, having its oppositely disposed ends narrowing to points, and having the ends of its base portion inclined towards the surface of such board to make a substantially obtuse angle therewith,.

length and in number to the angular portions of the base thus formed, each of said pieces being correspondingly wedge-shaped in cross-section and of substantially greater width than the depth of such incision, then arranging said pieces, respectively, so that their beveled ends abut, and forcing such pieces endwise towards each other and towards the base of such incision, whereby such pieces are secured in said incision with their ends in abutment, dressing off the ex-U cess portion of such plug inclsion.

9. The method ing a surface imperfection, characterized by cutting away such imperfection by, forming an elongated incision in such surface, and fitting into such incision a plug comprising a plurality of pieces, "one of said pieces being driven endwise, such incision.

10- The method of patching a board having a surface imperfection, characterizedbycutting away such imperfection by formlng not fitted into the "or patching aboard havand downwardly into' an elongatedincision in such surface, and

fitting into such incision a plug comprising a plurality of pieces, one of said pieces being driven endwise, and downwardly into such incision, said incision being wedge-shaped in section, and of proportions similar to the section of said incision.

11, The method of patchng a board having a surface imperfection, characterized by cutting awa such imperfection by forming an elongate incision in such surface, and fitting into such incision a plug comprising a plurality of pieces, one of vsaid pieces bein driven endwise, and downwardly into suc incision, said incision being Wedge-shaped in section, and cigar-shaped in plan, said latter piece being of uniform continuous, wedgeshaped section, andof proportions similar to the section of said incision, and driven inwardly from one of said cigar-shaped ends. JOHN C, DE PENNING. 

